Drill retainer



Nov. 18, 1924. 1,516,055

G, M. NELL DRILL RETAINER Filed July 27. 1923 Patented Nov. 18, 1924,

n sr 1 eusravn M. NELL, or CLEVELAND, oHro, essreivon TO THE CLEVELANDnoon DRILL COMPANY, or CLEVELAND, OHIO.

DRILL RETAINER.

Application filed July 27, 1923. Serial No. 654,176.

T 0 all whom it may concern:

Be it known that I, Gnsravn M. NELL, 'a citizen of the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented new and useful Improvements in Drill Retainers, of which thefollowing is a specification.

The present invention is directed to improvements in drill retainers foruse in connection with rock drills of the percussive type.

The primary object of they invention is to provide a novel and simpleform of retainer so constructed that complicated parts for holding thesame in its open or inoperative position are eliminated.

A further object of the inventionis to provide a retainer which isdurable, efficient in operation, cheap to manufacture, and one in whichthe drill steel will be effectively interlocked therewith to enable thesteel to be pulled from the hole when becoming stuck therein, provisionbeing made to absorb the shock upon the drill incident to the drillsteel striking retainer when not striking the work.

The above and other objects and advantages of my improvement will fullyappear from the following description taken in connection with theaccompanying drawing and be explicitly defined in the appended claims. Iwish it understood, however, that this disclosure is illustrative only,and that the principle of my invention can be embodied in theconstructions other than the one specified herein.

In the accompanying drawing 2" Figure 1 is a plan. View.

Figure 2 is a side elevation, showing the retainer in its open orinoperative position.

Referring to the drawing 1 designates the front head of a conventionalform of percussive drill, and upon apposite sides thereof are locatedoutwardly extended lugs 2,

' circular in cross section, and serving as the medium for pivotallyconnecting the retainer to the drill.

The retainer comprises a yoke 3 the bight portion thereof being providedwith a lateral open loop 1 adapted to embrace the drill steel 5 mountedfor rotary and reciprocatory movement in the front head 1, said loopbeing of such size as to prevent the dr1ll collar 6 from passingtherethrough.

inner ends formed with transverse heads 8,

in the outer sides of which are formed rec tangular recesses 9, thepurpose of which will appear later.

Rectangular blocks 10 are provided and have central circular bearings 11formed therethrough for pivotally receiving the lugs 2, said blocksbeing provided upon one of their .ends with solid projections'll. Theopposite ends of the blocks are formed with kerfs 12 which open into thebearing 11 and thereby split the projections 13 so as to norn'iallyspace the fingers 1d and 15 constituting the said projections. It willbe thus observed that the blocks are'capable of being expanded andcontracted owing to the presence of the kerfs 12, as the occasion mayrequire.

The projections 11 and the fingers M- and 15. of the projections 13 areprovided, respectively, with openings 16 which register with openings 17formed'in the ends of the heads 8, and it is in these registeredopenings that the paired retaining bolts 18 are engaged, the squareheads 19 of which being engaged flush against the adjacent ends of theouter portions of the blocks 10 when said heads are engaged with the.respective projections, whereby accidental rotation of said bolts areprevented.

The outer ends of the bolts 18 are threaded in the ends of theconnecting bars 20, said bars being disposed upon the outer sides of theside arms 7 of the yoke, there being coil springs 21 encircling thebolts and having their terminals respectively engaged with the ends ofthe heads 8 and ends of the bars 20, said springs tending to urge theheads inwardly so that the forward portions of the blocks 10 will beyieldably received in the recesses 9 of the heads 8.

The front head 1 is provided upon 0-pposite sides with recesses 22 inwhich the side arms 7 of the yoke engage, the inherent resiliency of theyoke causing the side arms to yieldingly engage said recesses, and inthis manner the yoke is held positively against accidental opening.

It will be apparent that the spring 21 which encircles the bolt 18 whichengage in the fingers 14 and 15 will urge the bars 20 forwardly, therebyexerting stress upon the fingers 1a to cause the same to approach thefingers 15 thus contracting the blocks 10 to cause the same tofrictionally and yieldably engage the lugs 2. Thus the retainer can beswung to its open position and will remain in a selected position owingto the normal contraction of the blocks with respect to the lugs.

It will be observed that when strain is applied to the yoke incident tothe engagement of the collar 6 with the loop at the yoke will moveforwardly against the ten sion of the springs. 21, and at which time theblocks 10 and heads 8 move relatively, the movement, however, will notbe sulficient to cause the forward portions of the blocks to disengagethe recesses 9 in which they slidahly engage.

What is claimed is 1. In a device of the class described, thecombination with a front head of a drill having l'ugs 'on the oppositesides thereof, of a drill steel retainer comprising a yoke, blockspivotally coi'inecte'd to the lugs, the side arms of the yoke beingslidably engaged with the blocks, and means for yieldably coi'inectingthe blocks with the lugs and the yoke with the blocks.

2. In a device of the class described, the combination. with a fronthead of a drill having lugs upon the opposite sides thereof, ofresilient blocks pivotally engaged with the lugs, a drill steel retainercomprising a yoke, and spring restrained bolts passing through the sidearms of the yoke and through the blocks. 7

3. In a device of the class described, the combination with a front headof a drill, of lugs upon opposite sides of the front head, bl'o'clespivotally connected with the lugs, said blocks having resilientlyconnected fingers carried thereby, a drill steel retainer comprising ayoke, the side arms thereof, being slidably connected with the blocks,spring restrained bolts yieldably connecting the yoke with the blocks,one of said bolts being co-oper'atively connected with the fingersgtohold the blocks normally in contracted engagement with the lugs, as andfor the purpose set forth.

4. In a device of the class described, the combination with a, fronthead of a drill, of blocks pivotally connected therewith, a drill steelretainer comprising a yoke, the side arms thereof being slidably andyieldably connected with the blocks, said blocks being c'ontractible forresilient engagement witll the pivotal connections with the front he'aIn testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

GUSTAVE M. NELL.

lVitness'es E. L. OLDEHAM, L. L. RioHARDsoN.

